A speech encoder is typically used to process noisy speech and tested with a moderate level of noise. Substantial background noises are common in speech communications, and noise suppressors are widely used for suppressing these background noises before the speech is encoded by a speech encoder. A noise suppressor improves the speech signal by reducing the level of noise, which may be used to improve voice signal quality. However, when noises are being removed from the initial audio signal, spectral and temporal modifications to the speech signal may be introduced in a manner that is not known to the speech encoder. Because the speech encoder may be tuned to a specific built-in noise suppressor, bypassing the original built-in noise suppressor or otherwise modifying the built-in suppressor may cause the speech encoder to misclassify speech and noise. This misclassification may result in wasting data and a suboptimal audio signal.